/Engine/Plugins/Runtime/XRBase/Source/XRBase/Public/MotionTrackedDeviceFunctionLibrary.h
Set whether motion tracked controllers activate on creation by default, or do not and must be explicitly activated.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category="Input|MotionTracking") static void SetIsControllerMotionTrackingEnabledByDefault ( bool Enable )